O'Byrne is a stay-at-home defenseman with tremendous size and reach. He likes to play a physical game and can deliver some big hits in open ice. However, he does not contibute much on offense and is rather immobile.- Erik K. Piri, EP

Career transactions
- 2013-09-02 • Signed by HC Lev Praha
- 2013-04-03 • Traded to the Toronto Maple Leafs for a 2014 4th round pick
- 2011-06-30 • Re-signed to a two-year contract by the Colorado Avalanche
- 2010-11-11 • Traded to the Colorado Avalanche for the rights to Michaël Bournival
- 2008-07-16 • Re-signed to a three-year contract by the Montreal Canadiens
- 2006-08-09 • Signed to a two-year contract by the Montreal Canadiens